Stenosis or occlusion of cerebral arteries can lead to ischemic stroke, accounting for 60%–70% of all strokes. Severe cases may result in patient mortality. The primary cause of ischemic stroke is atherosclerosis, which can affect both the internal carotid artery and the vertebral artery. Clinically, ischemic stroke may manifest as transient ischemic attack (TIA), reversible ischemic neurologic deficit (RIND), progressive stroke (PS), or complete stroke (CS). Some patients may remain asymptomatic, with carotid or vertebral artery stenosis detected incidentally through ultrasound examinations. Such early detection provides an effective means for identifying and preventing ischemic stroke.
Imaging Diagnostics
Carotid Artery Ultrasound Examination
Carotid ultrasound allows for the diagnosis of stenosis, atherosclerotic plaque, and other abnormalities in the carotid arteries.
Head CT
CT scans in the early stages of stroke can exclude intracerebral hemorrhage. However, brain infarctions often do not appear in early CT imaging. Infarcted areas may become visible 24–48 hours after stroke onset, typically without mass effects. CT angiography (CTA) allows high-resolution imaging of vessels from the aortic arch to the internal and external carotid arteries within seconds, while CT perfusion imaging (CTP) can provide perfusion information.
MRI
Ischemic brain regions become visible within four hours after stroke onset. When combined with magnetic resonance angiography (MRA), MRI can also detect arterial dissection.
DSA
Digital subtraction angiography (DSA) provides a detailed view of stenosis, occlusion, or tortuosity in cerebral arteries. It can also help exclude conditions such as aneurysms or vasculitis and may facilitate endovascular treatment.
Surgical Treatments
Carotid Endarterectomy (CEA)
This procedure involves surgically opening the wall of the internal carotid artery to directly remove atherosclerotic plaques, restoring the patency of the artery and reducing the risk of stroke. It is suitable for patients with severe extracranial internal carotid artery stenosis (≥50% stenosis), particularly when the stenotic segment is located below the mandibular angle and is surgically accessible.
Indications for Surgery
CEA is recommended for patients with asymptomatic carotid artery stenosis >70%. It is also preferred when anatomical challenges complicate endovascular treatment.
Carotid Artery Stenting (CAS)
Indications for Surgery
The indications include:
- Asymptomatic stenosis: Stenosis ≥70% accompanied by risk factors for ischemic complications, such as narrowing of the lumen, plaque embolization causing distal infarction, or plaque rupture leading to worsening stenosis. In these cases, stenting is needed.
- Symptomatic stenosis: Stenosis ≥50% in patients with recent transient ischemic attacks or a history of cerebral infarction within the past six months to one year.